I found that comment rather interesting as well. I don't own any TT engines yet but I sure wish I did. I have a number of OS engines & they are good engines. I like them all, but I've been so impressed with the performance of many of my friends TT engines that I've come to believe they give you a little more bang for your buck. At least here in the states where there is a $27 difference in price between the OS46AX & the TTPRO46. I read in one of these forums just the other day that in Aus. OS & TT are priced the same. Here in the states there is a noticeable price difference with OS being the more expensive engine. The next 46 or 61 engine I buy will be a TT PRO.